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991.
An efficient preconditioner for electromagnetic integral equations using predefined wavelet packet basis 总被引:1,自引:0,他引:1
Hai Deng Hao Ling 《Antennas and Propagation, IEEE Transactions on》2002,50(11):1633-1640
An approximate-inverse preconditioner based on the predefined wavelet packet (PWP) basis is proposed for the fast iterative solution of electromagnetic integral equations. The PWP basis is designed to achieve a sparse representation of the moment matrix and the preconditioner is constructed by inverting the block-diagonal approximation of the PWP-based moment matrix and transforming the results into the space domain. Numerical results show that the PWP preconditioner is effective in accelerating the convergence rate of iterative solution to moment equations. It is also demonstrated that by properly designing the block-diagonal matrix and computing the matrix elements, the total computational complexity and memory costs for the preconditioner can be kept to O(NlogN). 相似文献
992.
993.
Toliver P. Glesk I. Runser R.J. Kung-Li Deng Yu B.Y. Prucnal P.R. 《Lightwave Technology, Journal of》1998,16(12):2169-2180
This paper presents the design and experimental results of an optical packet-switching testbed capable of performing message routing with single wavelength time division multiplexed (TDM) packet bit rates as high as 100 Gb/s. The physical topology of the packet-switched optical networking demonstration (POND) node is based on an eight-node ShuffleNet architecture. The key enabling technologies required to implement the node such as ultrafast packet generation, high-speed packet demultiplexing, and efficient packet routing schemes are described in detail. The routing approach taken is a hybrid implementation in which the packet data is maintained purely in the optical domain from source to destination whereas control information is read from the packet header at each node and converted to the electrical domain for an efficient means of implementing routing control. The technologies developed for the interconnection network presented in this paper can be applied to larger metropolitan and wide area networks as well 相似文献
994.
A finite difference approximation to a
hierarchical size-structured model with nonlinear growth,
mortality and reproduction rates is developed.
Existence-uniqueness of the weak solution to the model is
established and convergence of the finite-difference approximation
is proved. Simulations indicate that the monotonicity assumption on the
growth rate is crucial for the global existence of weak solutions.
Numerical results testing the efficiency of this
method in approximating the long-time behavior of the model are
presented. 相似文献
995.
探讨了推广EZ模型的可能性,并给出了相应的模型中人群大小分布函数的形式解.研究表明金融市场中不同大小的人群数目的交易人的数目在重新标度后将具有最广泛的普适性行为
关键词:
金融物理
人群效应
主方程 相似文献
996.
We study the dynamic critical behavior of the local bond-update (Sweeny) dynamics for the Fortuin-Kasteleyn random-cluster model in dimensions d=2, 3 by Monte Carlo simulation. We show that, for a suitable range of q values, the global observable S2 exhibits "critical speeding-up": it decorrelates well on time scales much less than one sweep. In some cases the dynamic critical exponent for the integrated autocorrelation time is negative. We also show that the dynamic critical exponent zexp is very close (possibly equal) to the rigorous lower bound alpha/nu and quite possibly smaller than the corresponding exponent for the Chayes-Machta-Swendsen-Wang cluster dynamics. 相似文献
997.
Mathematical Programming - Functional constrained optimization is becoming more and more important in machine learning and operations research. Such problems have potential applications in... 相似文献
998.
Tong-Hui Deng Xing-Wei An Zi-Liang Lan Lei Chen Sai-yun Ye Zhi-Rong Zhong 《Annalen der Physik》2023,535(4):2200608
Nonclassical effects in mesoscopic systems have attracted much attention recently. In this paper, it is shown that multiphonon bundle emission can be observed in a strong-coupling cavity optomechanical system. Theoretical analysis shows that when the driving field is adjusted to nth-order sideband excitation, the coupling between the cavity mode and the vibrational mode leads to super-Rabi oscillations, and finally results in an n-phonon bundles emission. Based on the current technology, this process can work in a wide range of parameters. Numerical simulation confirms the validity of the derivation. It is thought that this physical mechanism broadens the applications of cavity optomechanical system in realm of quantum phononics, such as in quantum metrology and phonon laser. 相似文献
999.
Haobin Yang Ziyu Wang Zhifeng Tu Junjie Jiang Danlin Xu Zhenwu Mo Haiqi Huang Dongmei Deng 《Annalen der Physik》2023,535(9):2300167
This paper analytically and numerically proposes the propagation dynamics of the symmetric Pearcey Gaussian vortex beam (SPGVB) in the uniformly moving parabolic potential. The optical vortex located in the initial plane produces a vortex channel in the presence of the uniformly moving parabolic potential, called the vortex trajectory. The vortex trajectory can be manipulated dynamically by configuring different combinations of the parameters, and the optical intensity and the focal position can also be affected. Moreover, the spatial dynamic vortex trajectory is derived analytically, and the 2D on-axis and off-axis vortex scenarios are also presented. Our work expands the methods of the vortex trajectory manipulation and may broaden more practical potential applications in the particle manipulation. 相似文献
1000.
Hechong Chen Zehong Liang Xinyue Wang Yong Zhang Lingling Shui Dongmei Deng 《Annalen der Physik》2023,535(1):2200375
By applying a virtual source method, the exact and the paraxial solutions of the Swallowtail beams (SBs) that are governed by the inhomogeneous Helmholtz equation are introduced. The paraxial SBs generated experimentally possess both self-accelerating and self-focusing features. The parameters controlling the field distributions are discussed in theory. From the spectral representation of the Swallowtail wave, in the appropriate limit, the first four terms of the nonparaxial correction series for the (1+2)-dimensional Swallowtail waves that simplify to the SBs are obtained. 相似文献